I use a Pendle with the Bagman standard support. Can't say enough good things about it, really.

There are many guys in my rando club who use large saddlebags w/o supports, and I don't know how. The constant bump-bump-bump of my thighs against the leading edge of the bag would drive me nuts after 5 miles.

There is one downside to the Bagman support: Bag Sag!
Over time, your canvas bag will sink in around the support hoop base and you'll have 3 distinct sagging pouches.
There's 3 ways around this:
1) Always stuff enough crap in your bag to keep it fully formed. (not a good option)
2) Make an internal stiffener from paperboard (like a Berthoud) or coroplast. (Can be directly riveted to the base of the bag, or you can rivet in board-backed velcro strips to affix a removeable stiffener plate)
3) Make a shelf which attaches via zip-ties to the Bagman support (easiest option)